How to calculate calorie deficit for weight loss

If you have listened to health experts talk about weight loss, you must have heard that a calorie deficit is required to achieve weight loss. But what does calorie deficit mean, and how can you calculate it?

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Key takeaways:

  • Calorie deficit is a term used to describe when a person consumes fewer calories than their body burns in a day. Many people create a calorie deficit to lose weight.
  • You can calculate your body's calorie deficit by calculating your body's daily maintenance calories using methods like the Mifflin-St. Jeor equation for people​ AMAB multiplied by your BMR, or Mifflin-St. Jeor equation for people AFAB by your BMR. Subtract about 500 calories from your daily maintenance calorie to get the calorie deficit specific to your body.
  • Counting calories by keeping track of the number of calories you consume daily, eating less sugary or highly processed foods, and consuming lots of vegetables can help you achieve a calorie deficit.

A calorie deficit occurs when an individual consumes fewer calories in a day than the number of calories they burn.

To function each day, the body needs to burn a certain number of calories. The number of calories an individual needs every day is called maintenance calories. An individual's maintenance calorie will depend on factors like:

  • Age
  • Sex
  • Height
  • Weight
  • Physical activity levels
  • Body composition

There are three ways to create a calorie deficit. An individual can create a calorie deficit by increasing their level of physical activity. Another way to create a calorie deficit is by reducing the number of calories consumed. Doing both can also create a calorie deficit.

Why people create a calorie deficit

The primary reason people create calorie deficits is to lose weight. Except for people who go for surgeries, there is no other shortcut to weight loss aside from eating fewer calories than it takes for the body to maintain its current weight or burning more calories than consumed.

Many people seeking weight loss strive for calorie deficits as a strategy for weight loss. This strategy helps people achieve their weight-loss goals in a well-calculated manner. The rule is simply this: burn more calories than you consume or consume fewer calories than your daily maintenance calories.

How to calculate calorie deficit

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Before creating a calorie deficit, first calculate your body's daily calorie needs. The daily calorie need, also called maintenance calories, is the number of calories the body needs daily to maintain its weight. Daily calorie need can also be defined as the number of calories the body requires to perform basic metabolic functions and daily physical activities.

To calculate your daily caloric need, first find your basal metabolic rate (BMR) by using one of these formulas:

  • Mifflin-St. Jeor equation for people assigned male at birth (​AMAB) = (9.99 x weight in kg) + (6.25 x height in cm) – (4.92 x age) + 5
  • Mifflin-St. Jeor equation for people assigned female at birth (AFAB) =​ (9.99 x weight in kg) + (6.25 x height in cm) – (4.92 x age) – 161

Once your BMR is known, you can get the equivalent of your daily maintenance calorie by multiplying that figure by the number that corresponds with your activity level; e.g., people who participate in very light physical activity have an activity level of 1.3, while people who participate in heavy activity have an activity level of 1.8.

You can also find out your daily calorie needs using an online calorie calculator.

When your daily maintenance calorie need is known, you can calculate how many calorie deficits you should create by subtracting 500–1000 calories from that figure.

Using a calorie tracking app to track daily calorie intake is helpful for weight maintenance. It is also okay to talk to a doctor, a registered dietician, or a nutritionist to help make an accurate caloric intake estimate. The health professionals will tailor the caloric intake estimates based on each individual's lifestyle.

Creating a calorie deficit

A person can create a calorie deficit by eating fewer calories, increasing physical activity, or both.

To create a calorie deficit through food intake, daily maintenance calories, or the number of calories needed per week, will be determined first.

After calculating the daily maintenance calorie, the next step is to determine how much fat the individual wants to lose and how fast they want to lose weight.

One pound of body fat contains about 3,500 calories. This means that for a person to lose one pound of fat within seven days, they would need a deficit of 3,500 calories within that period of time. An easy way to achieve this is to create a 500-calorie deficit per day until the 7th day.

A person can create a calorie deficit of 6,000 calories a week. However, a calorie deficit shouldn't exceed 7,000 calories per week. According to the Centers for Disease Control and Prevention, it is best to lose weight gradually and steadily.

As a person loses weight, the maintenance calories will reduce over time, and there will be a need to adjust the caloric intake based on the individual's weight loss goals.

Tips for eating fewer calories

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Reducing calorie intake to create a calorie deficit doesn't take much. It doesn't necessarily require drastic or excessive changes. There are simple things you can do to reduce your calorie intake and help you lose weight.

Below are some helpful tips for eating fewer calories:

  • Eliminate intake of sugary beverages like fruit juices and soda.
  • Limit consumption of highly processed foods like fast foods and desserts.
  • Eat more home-cooked meals.
  • Reduce intake of alcoholic beverages.
  • Dish food with smaller sized plates.
  • Incorporate vegetables into your foods.
  • Eat more fruits and use them as snacks.
  • Drink enough water.

Counting calories

One way to keep track of calorie intake is by counting calories. Counting calories involves knowing how many calories you are eating.

For instance, if you are consuming a plate of rice with chicken and salad, it is important to know how many calories are contained in the rice, chicken, and salad, respectively. This helps you stick with your daily maintenance calories.

Keeping a food diary makes it easier to count calories. To use a food diary, a person has to write down every food consumed and also find out each food item's calorie count. It will also help to download an app that counts calories.

Some websites and apps help simplify the process of calorie counting. Here are some of the best websites or apps for counting calories:

Wrap up

A calorie deficit is a pathway to weight loss. A calorie deficit is created when a person consumes fewer calories than the body uses. A calorie deficit of 500 calories daily is effective for sustainable and healthy weight loss, and it is best not to exceed a calorie deficit of 1000 calories per day.

Calorie counting helps keep track of calorie intake. Also, reducing the consumption of highly processed foods is an effective strategy for weight loss.

Frequently Asked Questions (FAQs)

What is an appropriate calorie deficit for weight loss?

Losing weight gradually, rather than drastically, is more sustainable and healthier. So, an appropriate calorie deficit for weight loss should not go above 1000 calories, which is less than your daily maintenance calorie. Aim to subtract 500–1000 calories from your daily maintenance calorie to get an ideal calorie deficit.

What is the most accurate calorie calculator?

While you can calculate your calorie figures yourself, there are many tools and online devices that can help you do that more accurately and faster. Some great calorie calculators that make for increased accuracy include the Body Weight Planner, My Fitness Pal, and Lose It!

How do I know how many calories I burn a day?

There are different formulas you can use to calculate how many calories your body burns in a day. The formula you will use will often involve calculating either your BMR and multiplying it by your physical activity level number or calculating your resting metabolic rate (RMR) and multiplying it by your activity level number.